Not good... Yet another line available to me, and if I felt they were workable I'd use them. I don't because they have been historically inconsistent drops and wacky rates (too little in the front mostly).
Sam's arguably the best guy on here for suspension advice. He doesn't recommend ST springs for the reasons he specified, but if you're hell bent on buying them then he can sell them to you. Would you guys prefer being fed marketing BS disguised as advice? Because that's what you'd be getting from a lot of performance parts vendors.